Floor Request Based on an Organization Identifier Among Wireless Devices

ABSTRACT

A first off-network wireless device transmits first media traffic to a third off-network wireless device employing a first session. The first off-network wireless device receives a floor request message from a second off-network wireless device. The floor request message comprises an organization field identifier and an organization identifier. The first off-network wireless device determines a call priority based on the organization field identifier and the organization identifier. Transmission of the first media traffic to the third off-network wireless device is terminated based on the call priority. The first off-network wireless device starts transmission of second media traffic to the second off-network wireless device employing a second session.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/386,566, filed Apr. 17, 2019, which is a continuation of U.S. Pat.No. 10,271,370, which issued Apr. 23, 2019, which claims the benefit ofU.S. Provisional Application No. 62/294,734, filed Feb. 12, 2016, whichis hereby incorporated by reference in its entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present inventionare described herein with reference to the drawings.

FIG. 1 illustrates a block diagram of an example system 100 according tovarious embodiments.

FIG. 2 is a system diagram of an example communications system in whichone or more disclosed embodiments may be implemented.

FIG. 3 is a system diagram of an example wireless transmit/receive unit(WTRU) as per an aspect of an embodiment.

FIG. 4 is a system diagram of an example radio access network and corenetwork as per an aspect of an embodiment.

FIG. 5 is a block diagram of a base station and a wireless device as peran aspect of an embodiment.

FIG. 7 is a flow diagram of an example procedure for Model A discoveryas per an aspect of an embodiment.

FIG. 8 is a flow diagram showing an example procedures for theannouncing MCS UE as per an aspect of an embodiment.

FIG. 9 is a flow diagram showing an example procedures for themonitoring MCS UE as per an aspect of an embodiment.

FIG. 10 is a flow diagram showing an example match reporting procedureas per an aspect of an embodiment.

FIG. 11 is a flow diagram showing an example procedures for Model Bdiscovery as per an aspect of an embodiment.

FIG. 12 is a flow diagram showing an example procedure for thediscoveree MCS UE as per an aspect of an embodiment.

FIG. 13 is a flow diagram of an example procedure for discoverer MCS UEas per an aspect of an embodiment.

FIG. 14 is a flow diagram showing an example matched reporting procedureas per an aspect of an embodiment.

FIG. 15 is a block diagram of an example MCS UE-to-network relay as peran aspect of an embodiment.

FIG. 16 is a flow diagram showing an example IMS registration procedureof an MCS UE as per an aspect of an embodiment.

FIG. 17 is a flow diagram of an example IMS registration of an MCS UE asper an aspect of an embodiment.

FIG. 18 is a flow diagram shows an example MCS group session setup byMCS UE as per an aspect of an embodiment.

FIG. 19 is a flow diagram of an example MCS session setup by MCS UE A asper an aspect of an embodiment.

FIG. 20 is a flow diagram illustrating an example call flow as per anaspect of an embodiment.

FIG. 21 is an example flow diagram as per an aspect of an embodiment.

FIG. 22 is an example flow diagram showing MCPTT UE 1 engaged inseparate MCPTT group calls as per an aspect of an embodiment.

FIG. 23A is a diagram of an example floor control message tagged with anassociated organization value as per an aspect of an embodiment.

FIG. 23B is a diagram of an example floor control messages comprising anoptional parameter as per an aspect of an embodiment.

FIG. 24 is an example flow diagram showing MCPTT UE 1 engaged inseparate MCPTT group calls as per an aspect of an embodiment.

FIG. 25 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments are generally directed to critical communicationservice (e.g., A) that may involve use of wireless mobiletelecommunication cellular and/or wireless mobile broadbandtechnologies. Wireless mobile broadband technologies may includewireless technologies suitable for use with wireless devices and/or userequipment (UE), such as one or more third generation (3G), fourthgeneration (4G) or emerging fifth generation (5G) wireless standards,revisions, progeny and variants. Examples of wireless mobile broadbandtechnologies may include without limitation any of the Institute ofElectrical and Electronics Engineers (IEEE) 802.16m and 802.16pstandards, 3rd Generation Partnership Project (3GPP) Long Term Evolution(LTE) and LTE-Advanced (LTE-A) standards, and International MobileTelecommunications Advanced (IMT-ADV) standards, including theirrevisions, progeny, and variants. Other suitable examples may include,without limitation, Global System for Mobile Communications(GSM)/Enhanced Data Rates for GSM Evolution (EDGE) technologies,Universal Mobile Telecommunications System (UMTS)/High Speed PacketAccess (HSPA) technologies, Worldwide Interoperability for MicrowaveAccess (WiMAX) or the WiMAX II technologies, Code Division MultipleAccess (CDMA) 2000 system technologies (e.g., CDMA2000 IxRTT, CDMA2000EV-DO, CDMA EV-DV, and so forth), High Performance Radio MetropolitanArea Network (HIPERMAN) technologies as defined by the EuropeanTelecommunications Standards Institute (ETSI) Broadband Radio AccessNetworks (BRAN), Wireless Broadband (WiBro) technologies, GSM withGeneral Packet Radio Service (GPRS) system (GSM/GPRS) technologies, HighSpeed Downlink Packet Access (HSDPA) technologies, High Speed OrthogonalFrequency-Division Multiplexing (OFDM) Packet Access (HSOPA)technologies, High-Speed Uplink Packet Access (HSUPA) systemtechnologies, 3 GPP Rel. 8, 9, 10 or 11 of LTE/System ArchitectureEvolution (SAE), and so forth. The examples are not limited in thiscontext. In this disclosure, the term “critical” is being employed as aterm of art as disclosed, for example, in various communicationspecifications and is therefore not intended to otherwise limit thescope of the claims.

By way of example and not limitation, various examples may be describedwith specific reference to various 3 GPP radio access network (RAN)standards, such as the 3 GPP Universal Terrestrial Radio Access Network(UTRAN), the 3 GPP Evolved Universal Terrestrial Radio Access Network(E-UTRAN) and 3GPP's suite of UMTS and LTE/LTE-Advanced TechnicalSpecifications (in case of LTE/LTE-Advanced collectively “3GPP LTESpecifications” according to the 36 Series of Technical Specifications),and IEEE 802.16 standards, such as, for example, the IEEE 802.16-2009standard and current third revision to IEEE 802.16 referred to as“802.16 Rev3” consolidating standards 802.16-2009, 802.16h-2010 and802.16m-2011, and the IEEE 802.16p draft standards including IEEEP802.16.1b/D2 January 2012 titled “Draft Amendment to IEEE Standard forWirelessMAN-Advanced Air Interface for Broadband Wireless AccessSystems, Enhancements to Support Machine-to-Machine Applications”(collectively “IEEE 802.16 Standards”), and any drafts, revisions orvariants of the 3 GPP LTE Specifications and the IEEE 802.16 Standards.Although some embodiments may be described as a 3GPP LTE Specificationsor IEEE 802.16 Standards system by way of example and not limitation, itmay be appreciated that other types of communications system may beimplemented as various other types of mobile broadband communicationssystems and standards. The examples are not limited in this context.

As contemplated in the present disclosure, mission critical service(MCS) may support an enhanced mission critical push-to-talk (MCPTT)service, an enhanced mission critical video (MCVIDEO) service, anenhanced mission critical data/message (MCDATA) service, and/or thelike. An MCS service may be suitable for mission critical scenarios andmay be based upon 3GPP EPS services. MCS may typically be a sessioninitiation protocol (SIP) based service that may be provided via acentralized MCS server residing in a network (e.g., a 3GPP EPS network).The MCS server may be an IP Multimedia Subsystem (IMS) applicationserver, but the MCS server may also be a non-IMS based SIP server. Userequipment (UEs) may directly attach to the network to receive criticalcommunication services from an MCS server. Some UEs may also utilizeProximity Services (ProSe) capabilities to indirectly attach to thenetwork through a relay UE. UEs utilizing ProSe capabilities may beoutside of a coverage area of the network and may be referred to asremote UEs.

FIG. 1 illustrates a block diagram of an example system 100 according tovarious embodiments. According to an embodiment, elements of system 100may be arranged for providing critical communication services to one ormore UEs (e.g. UE 130, UE 140 and UE 150). These critical communicationservices may comprise MCS services as specified in, for example, 3GPPtechnical specification (TS) 22.179, entitled “Technical SpecificationGroup Services and System Aspects; MCS over LTE, Stage 1”, Release 13,V13.0.1, published in January of 2015, and/or previous or subsequentreleases or versions (hereinafter referred to as 3GPP TS 22.179). Forexample, as shown in FIG. 1, a network 101 may include an MCS server 120that may serve as centralized server to enable network 101 to provide aSIP -based critical communication service to UEs 130, 140 or 150. MCSserver 120 may be arranged as, for example, an IMS application server ora non-IMS based SIP server.

According to an embodiment, access/core 190 may comprise elements ofnetwork 101 typically associated with 3GPP E-UTRAN access and 3GPPE-UTRAN core elements. For example, a UE such as UE 130 may gain accessto network 101 via Uu 117 coupled to evolved Node B (eNB) 102. Also, asshown in FIG. 1, MCS server 120 may couple to various access/core 190elements. For example, MCS server 120 may couple to a policy andcharging rules function (PCRF) 111 via 111. Link 111 may represent an Rxinterface reference point. MCS server 120 may also couple to a servinggateway/packet data gateway (SGW/PWG) 112 via SGi 113. SGi 113 mayrepresent an SGi interface reference point. (According to variousembodiments, an interface may comprise and/or be a reference point). MCSserver 120 may also couple to a broadcast/multicast -service center(BM-SC) 114 via MB2 115. MB2 115 may represent an MB2 reference point.

Mobile management entity (MME) 104 and multimedia broadcast/multicastservice gateway (MBMS GW) 106 may provide core 3 GPP E-UTRAN services toMCS server 120 and/or UEs 130, 140 and 150 to facilitate network 101 inproviding critical communication services.

According to an embodiment, UE 130 may attach directly to MCS server120. UE 130 may comprise an MCS client that may be arranged as a SIP-based MCS client for communication with MCS server 120. MCS server 120may be arranged as a type of group communication service applicationserver (GCS AS) and GC1 173 may represent a GC1 reference point throughwhich MCS server 120 couples with MCS client at UE 130.

According to an embodiment, UEs out of network coverage of network 101may still be able to obtain critical communication service by couplingthrough UEs serving as UE-to-network relays such as UE 130. For example,UE 150 may be able to indirectly couple to MCS server 120 via a firstlink 151 between UE 150 and UE 130 and through a second link (GC1 173)between UE 130 and MCS server 120.

According to an embodiment, UE 130 acting as an UE-to-network relay mayrelay traffic from MCS server 120 for authorized UEs and/or authorizedgroups of UEs (e.g., belonging to an MCS group). UE 130 may act as anUE-to-network relay for groups of which it is not a member. As such, arelay UE, such as UE 130, may comprise logic and/or features to enablethe relay UE to act as a node between an MCS server and a remote UE suchas UE 150 via link 151.

According to an embodiment, critical communication content may bedelivered to directly coupled UEs such as UEs 130 or 140 in either aunicast mode (e.g., via EPS bearers) and/or in multicast mode (e.g., viaevolved MBMS (eMBMS) bearers). Use of eMBMS bearers may be justified incases where a sufficient number of UEs are physically located within asame coverage area or cell. When the number of UEs in a cell is low,unicast delivery via EPS may be more efficient compared to eMBMS ormulticast delivery. MCS server 120 may comprise logic and/or featurescapable of monitoring the number of UEs in a cell and then adjust adelivery mode accordingly.

According to an embodiment, as part of ProSe capabilities, UE 130 and UE150 may establish a direct link 151. UE 130 may couple to MCS server 120through GC1 173. Alternatively, UE 150 may couple to MCS server 120 via:(1) link 151 between UE 150 and UE 130; (2) link 131 between UE 130 andUE 140; and (3) GCI 174 between UE 140 to MCS Server 120. Establishmentof the direct link may comprise relay discovery, mutual authenticationand IP address assignment. Establishment of the direct link may compriseUE 130 and UE 150 setting up a wireless local area network (WLAN) directconnection. The WLAN direct connection may be arranged to operateaccording to Ethernet wireless standards (including progenies andvariants) associated with the IEEE Standard for Informationtechnology-Telecommunications and information exchange betweensystems—Local and metropolitan area networks—Specific requirements Part1 1: WLAN Media Access Controller (MAC) and Physical Layer (PHY)Specifications, published March 2012, and/or later versions of thisstandard (“IEEE 802.11”). According to an embodiment, following the samelogic as mentioned above for MCS server 120 selecting a unicast ormulticast delivery mode, logic and/or features of a relay UE such as UE130 and/or 140 may choose a unicast or multicast delivery mode to relayinformation (e.g., critical communication content) to one or more remoteUEs such as UE 150 and/or each other.

A direct link between UEs 140 and 130 may be established via, forexample, a PC5 interface (e.g. 131). The PC5 interface may beselectively chosen to communicate information. It may be possible to useunicast delivery via the LTE-Uu interface.

Concepts expressed herein may be implemented in connection with cellulartelephones and/or other types of User Equipment (UE) used oncommunication networks, and particularly wireless communicationnetworks. Described below are one or more example communication networksand related equipment within which at least some of the aspects of theherein described concepts may be implemented.

FIG. 2 is a diagram of an example communications system 200 in which oneor more disclosed embodiments may be implemented. The communicationssystem 200 may comprise a multiple access system configured to providecontent, such as voice, data, video, messaging, broadcast, etc., tomultiple wireless users. The communications system 200 may enablemultiple wireless users to access such content through the sharing ofsystem resources, including, for example, wireless bandwidth. Forexample, communications systems 200 may employ one or more channelaccess processes, such as code division multiple access (CDMA), timedivision multiple access (TDMA), frequency division multiple access(FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), and/orthe like.

As shown in FIG. 2, the communications system 200 may comprise wirelesstransmit/receive units (WTRUs) 202A, 202B, 202C, 202D, a radio accessnetwork (RAN) 204, a core network 206, the Internet 210, and/or othernetworks 212. It will be appreciated that the disclosed embodimentscontemplate various numbers of WTRUs, base stations, networks, and/ornetwork elements. Each of the WTRUs 202A, 202B, 202C, 202D may beconfigured to operate and/or communicate in a wireless environment. Byway of example, WTRUs 202A, 202B, 202C, 202D may be configured totransmit and/or receive wireless signals and may comprise user equipment(UE), a mobile station, a fixed or mobile subscriber unit, a pager, acellular telephone, a personal digital assistant (PDA), a smartphone, alaptop, a netbook, a personal computer, a wireless sensor, consumerelectronics, combinations thereof, and/or the like.

The communications systems 200 may also comprise a base station 214Aand/or base station 214B. Each of the base stations 214A, 214B may be atype of device configured to wirelessly interface with at least one ofthe WTRUs 202A, 202B, 202C, 202D to facilitate access to one or morecommunication networks, such as core network 206, Internet 210 and/ornetworks 212. By way of example, base stations 214A and/or 214B maycomprise a base transceiver station (BTS), a Node-B, an eNode B, a HomeNode B, a Home eNode B, a site controller, an access point (AP), awireless router, combinations thereof, and/or the like. While basestations 214A and 214B are each depicted as a single element, it will beappreciated that base stations 214A and 214B may comprise variousnumbers of interconnected base stations and/or network elements.

As illustrated, base station 214A may be a part of the RAN 204, whichmay also comprise other base stations and/or network elements (notshown), such as, for example, a base station controller (BSC), a radionetwork controller (RNC), relay nodes, combinations thereof, and/or thelike. Base station 214A and/or the base station 214B may be configuredto transmit and/or receive wireless signals within a particulargeographic region, which may be referred to as a cell (not shown). Thecell may be further divided into cell sectors. For example, the cellassociated with the base station 214A may be divided into three sectors.Thus, according to an embodiment, base station 214A may comprise threetransceivers, i.e., one for each sector of the cell. According to anembodiment, base station 214A may employ multiple-input multiple output(MIMO) technology and, therefore, may utilize multiple transceivers foreach sector of the cell.

Base stations 214A and/or 214B may communicate with one or more of theWTRUs (e.g. 202A, 202B, 202C, and 202D) over an air interface (e.g.216A, 216B, (216C and/or 216E), and 216D, respectively), which maycomprise a wireless communication link (e.g., radio frequency (RF),microwave, infrared (IR), ultraviolet (UV), visible light, etc.). An airinterface (e.g. 216A, 216B, 216C, 216D, 216E, 216F and 216G) may beestablished employing a suitable radio access technology (RAT).

More specifically, as noted above, communications system 200 maycomprise a multiple access system and may employ one or more channelaccess schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, combinationsthereof, and/or the like. For example, base station 214A in the RAN 204and WTRUs 202A, 202B, and 202C may implement a radio technology such asUniversal Mobile Telecommunications System (UMTS) Terrestrial RadioAccess (UTRA), which may establish air interface (e.g. 202A, 202B, and202C) employing wideband CDMA (WCDMA). WCDMA may comprise communicationprotocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA(HSPA+). HSPA may comprise High-Speed Downlink Packet Access (HSDPA)and/or High-Speed Uplink Packet Access (HSUPA).

According to an embodiment, base station 214A and WTRUs 202A, 202B, 202Cmay implement a radio technology such as Evolved UMTS Terrestrial RadioAccess (E-UTRA), which may establish air interface (e.g. 216A, 216B, and216C, respectively) employing Long Term Evolution (LTE) and/orLTE-Advanced (LTE-A).

According to an embodiment, base station 214A and WTRUs 202A, 202B, 202Cmay implement radio technologies such as IEEE 802.16 (i.e., WorldwideInteroperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1×,CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95(IS-95), Interim Standard 856 (IS-856), Global System for Mobilecommunications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSMEDGE (GERAN), combinations thereof, and/or the like.

Base station 214B in FIG. 2 may comprise a wireless router, Home Node B,Home eNode B, or an access point, for example, and may utilize a RAT forfacilitating wireless connectivity in a localized area, such as a placeof business, a home, a vehicle, a campus, combinations thereof, and/orthe like. According to an embodiment, base station 214B and WTRUs 202C,202D may implement a radio technology such as IEEE 802.11 to establish awireless local area network (WLAN). According to an embodiment, basestation 214B and WTRUs 202C and 202D may implement a radio technologysuch as IEEE 802.15 to establish a wireless personal area network(WPAN). According to an embodiment, base station 214B and WTRUs 202C and202D may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE,LTE-A, etc.) to establish a picocell or femtocell. As shown in FIG. 2,base station 214B may have a direct connection to the Internet 210.Thus, base station 214B may not be required to access the Internet 210via the core network 206.

The RAN 204 may be in communication with the core network 206, which maybe a type of network configured to provide voice, data, applications,and/or voice over internet protocol (VoIP) services to one or more ofthe WTRUs 202A, 202B, 202C, and 202D. For example, core network 206 mayprovide call control, billing services, mobile location-based services,pre-paid calling, Internet connectivity, video distribution, etc.,and/or perform high-level security functions, such as userauthentication. Although not shown in FIG. 2, it anticipated thataccording to an embodiment, RAN 204 and/or core network 206 may be indirect or indirect communication with other RANs that employ the sameRAT as the RAN 204 or a different RAT. For example, in addition to beingconnected to the RAN 204, which may utilize an E-UTRA radio technology,the core network 206 may also be in communication with another RAN (notshown).

Core network 206 may serve as a gateway for the WTRUs 202A, 202B, 202Cand/or 202D to access the PSTN 208, the Internet 210 and/or othernetworks 212. The Internet 210 may comprise a global system ofinterconnected computer networks and devices that use commoncommunication protocols, such as the transmission control protocol(TCP), user datagram protocol (UDP) and the internet protocol (IP) inthe TCP/IP internet protocol suite. Other networks 212 may comprisewired and/or wireless communications networks owned and/or operated byother service providers. For example, the networks 212 may compriseanother core network connected to one or more RANs, which may employ thesame RAT as the RAN 204 or a different RAT.

Some or all of the WTRUs 202A, 202B, 202C, and 202D in thecommunications system 200 may comprise multi-mode capabilities (i.e.,the WTRUs 202A, 202B, 202C, and 202D may comprise multiple transceiversfor communicating with different wireless networks over differentwireless links). For example, example WTRU 300 shown in FIG. 3 may beconfigured to communicate with base station 214A, which may employ acellular-based radio technology, and with the base station 214B, whichmay employ an IEEE 802 radio technology.

FIG. 3 is a system diagram of an example WTRU 300. As shown in FIG. 3,example WTRU 300 may comprise a processor 318, a transceiver 320, atransmit/receive element 322, a speaker/microphone 324, a keypad 326, adisplay/touchpad 328, non-removable memory 330, removable memory 332, apower source 334, a global positioning system (GPS) chipset 336, andother peripherals 338. It will be appreciated that the WTRU 300 maycomprise a sub-combination of the foregoing elements while remainingconsistent with an embodiment. For example, an WRTU 300 embodiment maybe implemented without one or more of the dashed elements 324, 328, 336and/or 332.

The processor 318 may be a general purpose processor, a special purposeprocessor, a conventional processor, a digital signal processor (DSP), aplurality of microprocessors, one or more microprocessors in associationwith a DSP core, a controller, a microcontroller, Application SpecificIntegrated Circuits (ASICs), Field Programmable Gate Array (FPGAs)circuits, any other type of integrated circuit (IC), a state machine,and the like. Processor 318 may perform signal coding, data processing,power control, input/output processing and/or other functionality thatenables example WTRU 300 to operate in a wireless environment. Processor318 may be coupled to the transceiver 320, which may be coupled to thetransmit/receive element 322. While FIG. 3 depicts elements such as, forexample, processor 318 and transceiver 320 as separate components, itwill be appreciated that the elements such as processor 318 and thetransceiver 320 may be integrated together in an electronic packageand/or chip. While FIG. 3 depicts elements such as, for example,processor 318 and transceiver 320 as individual components, it will beappreciated that the elements such as processor 318 and the transceiver320 may be implemented as a collection of other elements.

The transmit/receive element 322 may be configured to transmit signalsto, or receive signals from, a base station (e.g., the base station214A) over the air interface 316. For example, in an embodiment, thetransmit/receive element 322 may be an antenna configured to transmitand/or receive RF signals. According to an embodiment, thetransmit/receive element 322 may be an emitter/detector configured totransmit and/or receive IR, UV, or visible light signals, for example.According to an embodiment, the transmit/receive element 322 may beconfigured to transmit and receive both RF and light signals. It will beappreciated that the transmit/receive element 322 may be configured totransmit and/or receive any combination of wireless signals.

In addition, although the transmit/receive element 322 is depicted inFIG. 3 as a single element, example WTRU 300 may comprise any number oftransmit/receive elements 322. More specifically, example WTRU 300 mayemploy MIMO technology. Thus, according to an embodiment, example WTRU300 may comprise two or more transmit/receive elements 322 (e.g.,multiple antennas) for transmitting and receiving wireless signals overthe air interface 316.

Transceiver 320 may be configured to modulate signals that are to betransmitted by transmit/receive element 322 and to demodulate signalsreceived by transmit/receive element 322. As noted above, example WTRU300 may have multi-mode capabilities. Thus, the transceiver 320 maycomprise multiple transceivers for enabling example WTRU 300 tocommunicate via multiple RATs, such as E-UTRA and IEEE 802.11, forexample.

Processor 318 of example WTRU 300 may be coupled to, and may receiveuser input data from, for example, the speaker/microphone 324, thekeypad 326 and/or the display/touchpad 328 (e.g., a liquid crystaldisplay (LCD) display unit or organic light-emitting diode (OLED)display unit). Processor 318 may output user data to, for example, thespeaker/microphone 324, the keypad 326 and/or the display/touchpad 328.Processor 318 may access information from, and store data in, a type ofsuitable memory, such as the non-removable memory 330 and/or theremovable memory 332. The non-removable memory 330 may compriserandom-access memory (RAM), read-only memory (ROM), a hard disk, and/orother type of memory storage device. The removable memory 332 maycomprise a subscriber identity module (SIM) card, a memory stick, asecure digital (SD) memory card, and/or the like. According to anembodiment, processor 318 may access information from, and store datain, memory that is not physically located on example WTRU 300, such ason a server or a home computer (not shown).

Processor 318 may receive power from the power source 334, and may beconfigured to distribute and/or control the power to the othercomponents in example WTRU 300. Power source 334 may be a suitabledevice for powering example WTRU 300. For example, power source 334 maycomprise one or more dry cell batteries (e.g., nickel-cadmium (NiCd),nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion),etc.), solar cells, fuel cells, combinations thereof, and/or the like.

Processor 318 may also be coupled to GPS chipset 336, which may beconfigured to provide location information (e.g., longitude andlatitude) regarding the current location of example WTRU 300. Inaddition to, and/or in lieu of, the information from the GPS chipset336, example WTRU 300 may receive location information over the airinterface 316 from a base station (e.g., base stations 214A, 214B)and/or determine a location based on the timing of the signals beingreceived from two or more nearby base stations. It will be appreciatedthat the WTRU 300 may acquire location information by way of othersuitable location-determination process(es) while remaining consistentwith an embodiment.

Processor 318 may further be coupled to other peripherals 338, which maycomprise one or more software and/or hardware modules that provideadditional features, functionality, and/or wired or wirelessconnectivity. For example, peripherals 338 may comprise, for example, anaccelerometer, an e-compass, a satellite transceiver, a digital camera(for photographs or video), a universal serial bus (USB) port, avibration device, a television transceiver, a hands free headset, aBluetooth™ module, a frequency modulated (FM) radio unit, a digitalmusic player, a media player, a video game player module, an Internetbrowser, a combination thereof, and/or the like.

FIG. 4 is a system diagram of an example communications systemcomprising an example RAN 404 and an example core network 406. Thisexample communications system is disclosed for example purposes.Variations in communications systems may be implemented within the scopeof the embodiment. In this example embodiment, RAN 404 may employ anE-UTRA radio technology to communicate with the WTRUs 402A, 402B and/or402C over air interfaces 416A, 416 b and/or 416C respectively. RAN 404may be in communication with the core network 406.

Example RAN 404 may comprise eNBs 460A, 460B and/or 460C, though it willbe appreciated that the RAN 404 may comprise various numbered of eNBswhile remaining consistent with an embodiment. The eNBs 460A, 460Band/or 460C may each comprise one or more transceivers for communicatingwith the WTRUs 402A, 402B and/or 402C over air interface 416A, 416Band/or 416C respectively. In an embodiment, the eNBs 460A, 460B and/or460C may implement MIMO technology. Thus, the eNB 460A, for example, mayuse multiple antennas to transmit wireless signals to, and receivewireless signals from, example WTRUs 402A.

Some WTRUs may be configured to communicate with each other directly.For example, as illustrated, WTRU 402E may be configured to communicatewith example WTRU 402B and/or example WTRU 402C over the air interfaces416F and/or 416E, respectively. Similarly, example WTRU 402D may beconfigured to communicate with example WTRU 402C over the air interfaces416D.

Each of the eNBs 460A, 460B, and/or 460C may be associated with aparticular cell (not shown) and may be configured to handle radioresource management decisions, handover decisions, scheduling of usersin the uplink and/or downlink, and the like. As shown in FIG. 4, theeNBs 460A, 460B and/or 460C may communicate with one another over, forexample: an X2 interface, a reference point, and/or the like.

Example core network 406 shown in FIG. 4 may comprise a mobilitymanagement gateway (MME) 462, a serving gateway 464, a packet datanetwork (PDN) gateway 466, and/or the like. While each of the foregoingelements are depicted as part of the core network 406, it will beappreciated that various elements operating in a core network (e.g. 406)may be owned and/or operated by an entity other than the core networkoperator.

The MME 462 may be connected to each of the eNBs 460A, 460B, 460C in RAN404 via an 51 interface, a reference point, and/or the like and mayserve as a control node. For example, the MME 462 may be responsible forauthenticating users of the WTRUs 402A, 402B, 402C, 402D and/or 402E,bearer activation/deactivation, selecting a particular serving gatewayduring an initial attach of the WTRUs 402A, 402B, 402C, 402D and/or402E, and/or the like. The MME 462 may also provide a control planefunction for switching between the RAN 404 and other RANs (not shown)that employ other radio technologies, such as, for example, GSM and/orWCDMA.

Serving gateway 464 may be connected to each of the eNode Bs 460A, 460Band/or 460C in the RAN 404 via an S1 interface, a reference point,and/or the like. The serving gateway 464 may generally route and forwarduser data packets to and from the WTRUs 402 a, 402B and/or 402C. Theserving gateway 464 may also perform other functions, such as anchoringuser planes during inter-eNode B handovers, triggering paging whendownlink data is available for the WTRUs 402A, 402B and/or 402C,managing and storing contexts of the WTRUs 402A, 402B and/or 402C,and/or the like.

The serving gateway 464 may also be connected to the PDN gateway 466,which may provide the WTRUs 402 a, 402B and/or 402C with access topacket-switched networks, such as the Internet 410, to facilitatecommunications between the WTRUs 402A, 402B and/or 402C and IP-enableddevices.

Example core network 406 may facilitate communications with othernetworks. For example, core network 406 may provide the WTRUs 402A, 402Band 402C with access to circuit-switched networks to facilitatecommunications between the WTRUs 402A, 402B, 402C and traditionalland-line communications devices. For example, the core network 406 maycomprise, and/or may communicate with, an IP gateway (e.g., an IPmultimedia subsystem (IMS) server) that serves as an interface betweenthe core network 406 and a PSTN. In addition, the core network 406 mayprovide the WTRUs 402A, 402B, 402C with access to the networks 412,which may comprise other wired or wireless networks that are ownedand/or operated by other service providers.

FIG. 5 is an example block diagram of a base station 501 and a wirelessdevice 506, as per an aspect of an embodiment of the present invention.A communication network 500 may comprise at least one base station 501and at least one wireless device 506. The base station 501 may compriseat least one communication interface 502, at least one processor 503,and at least one set of program code instructions 505 stored innon-transitory memory 504 and executable by the at least one processor503. The wireless device 506 may comprise at least one communicationinterface 507, at least one processor 508, and at least one set ofprogram code instructions 510 stored in non-transitory memory 509 andexecutable by the at least one processor 508. Communication interface502 in base station 501 may be configured to engage in communicationwith communication interface 507 in wireless device 506 via acommunication path that comprises at least one wireless link 511.Wireless link 511 may be a bi-directional link. Communication interface507 in wireless device 506 may also be configured to engage in acommunication with communication interface 502 in base station 501. Basestation 501 and wireless device 506 may be configured to send andreceive data over wireless link 511 using multiple frequency carriers.According to some of the various aspects of embodiments, transceiver(s)may be employed. A transceiver is a device that comprises both atransmitter and receiver. Transceivers may be employed in devices suchas wireless devices, base stations, relay nodes, and/or the like.

An interface may be a hardware interface, a firmware interface, asoftware interface, and/or a combination thereof. The hardware interfacemay comprise connectors, wires, electronic devices such as drivers,amplifiers, and/or the like. A software interface may comprise codestored in a memory device to implement protocol(s), protocol layers,communication drivers, device drivers, combinations thereof, and/or thelike. A firmware interface may comprise a combination of embeddedhardware and code stored in and/or in communication with a memory deviceto implement connections, electronic device operations, protocol(s),protocol layers, communication drivers, device drivers, hardwareoperations, combinations thereof, and/or the like.

The term configured may relate to the capacity of a device whether thedevice is in an operational or non-operational state. Configured mayalso refer to specific settings in a device that effect the operationalcharacteristics of the device whether the device is in an operational ornon-operational state. In other words, the hardware, software, firmware,registers, memory values, and/or the like may be “configured” within adevice, whether the device is in an operational or nonoperational state,to provide the device with specific characteristics. Terms such as “acontrol message to cause in a device” may mean that a control messagehas parameters that may be used to configure specific characteristics inthe device, whether the device is in an operational or non-operationalstate.

According to some of the various aspects of embodiments, an LTE networkmay comprise a multitude of base stations, providing a user planePDCP/RLC/MAC/PHY and control plane (RRC) protocol terminations towardsthe wireless device. The base station(s) may be interconnected withother base station(s) (e.g. employing an X2 interface, reference point,and/or the like). The base stations may also be connected employing, forexample, an S1 interface to an EPC. For example, the base stations maybe interconnected to the MME employing the S1-MME interface, referencepoint, and/or the like and to the Serving Gateway (S-G) employing theS1-U reference point. The S1 interface, reference point, and/or the likemay support a many-to-many relation between MMEs/Serving Gateways andbase stations. A base station may comprise many sectors for example: 1,2, 3, 4, or 6 sectors. A base station may comprise many cells, forexample, ranging from 1 to 50 cells or more. A cell may be categorized,for example, as a primary cell or secondary cell. At RRC connectionestablishment/re-establishment/handover, one serving cell may providethe NAS (non-access stratum) mobility information (e.g. TAI), and at RRCconnection re-establishment/handover, one serving cell may provide thesecurity input. This cell may be referred to as the Primary Cell(PCell). In the downlink, the carrier corresponding to the PCell may bethe Downlink Primary Component Carrier (DL PCC), while in the uplink, itmay be the Uplink Primary Component Carrier (UL PCC). Depending onwireless device capabilities, Secondary Cells (SCells) may be configuredto form together with the PCell a set of serving cells. In the downlink,the carrier corresponding to an SCell may be a Downlink SecondaryComponent Carrier (DL SCC), while in the uplink, it may be an UplinkSecondary Component Carrier (UL SCC). An SCell may or may not have anuplink carrier.

A cell, comprising a downlink carrier and optionally an uplink carrier,may be assigned a physical cell ID and a cell index. A carrier (downlinkor uplink) may belong to only one cell. The cell ID or Cell index mayalso identify the downlink carrier or uplink carrier of the cell(depending on the context it is used). In the specification, cell ID maybe equally referred to a carrier ID, and cell index may be referred tocarrier index. In implementation, the physical cell ID or cell index maybe assigned to a cell. A cell ID may be determined using asynchronization signal transmitted on a downlink carrier. A cell indexmay be determined using RRC messages. For example, when thespecification refers to a first physical cell ID for a first downlinkcarrier, the specification may mean the first physical cell ID is for acell comprising the first downlink carrier. The same concept may applyto, for example, carrier activation. When the specification indicatesthat a first carrier is activated, the specification may equally meanthat the cell comprising the first carrier is activated.

Embodiments may be configured to operate as needed. The disclosedmechanism may be performed when certain criteria are met, for example,in a wireless device, a base station, a radio environment, a network, acombination of the above, and/or the like. Example criteria may bebased, at least in part, on for example, traffic load, initial systemset up, packet sizes, traffic characteristics, a combination of theabove, and/or the like. When the one or more criteria are met, variousexample embodiments may be applied. Therefore, it may be possible toimplement example embodiments that selectively implement disclosedprotocols.

A base station may communicate with a mix of wireless devices. Wirelessdevices may support multiple technologies, and/or multiple releases ofthe same technology. Wireless devices may have some specificcapability(ies) depending on its wireless device category and/orcapability(ies). A base station may comprise multiple sectors. When thisdisclosure refers to a base station communicating with a plurality ofwireless devices, this disclosure may refer to a subset of the totalwireless devices in a coverage area. This disclosure may refer to, forexample, a plurality of wireless devices of a given LTE release with agiven capability and in a given sector of the base station. Theplurality of wireless devices in this disclosure may refer to a selectedplurality of wireless devices, and/or a subset of total wireless devicesin a coverage area which perform according to disclosed methods, and/orthe like. There may be a plurality of wireless devices in a coveragearea that may not comply with the disclosed methods, for example,because those wireless devices perform based on older releases of LTEtechnology.

In order to set up a session for a mission critical service (MCS), wherethe mission critical service may be mission critical push-to-talk(MCPTT), the MCS UEs affiliated to MCS groups may first discover eachother. This discovery may be a restricted discovery since MCS is apublic safety feature. In the restricted discovery, the discoverer UEsand discoveree UEs may be authorized by being pre-provisioned with oneor more parameters for the discovery procedure.

Examples for ProSe direct discovery methods are Model A and Model B.

Model A may include the following examples two roles for theProSe-enabled UEs that are participating in ProSe Direct Discovery:Announcing UE: a) The UE announces certain information that may be usedby UEs in proximity that have permission to discover. b) Monitoring UE:The UE that monitors certain information of interest in proximity ofannouncing UEs.

In Model A the announcing UE may broadcast discovery messages atdiscovery intervals (e.g. pre-defined intervals) and the monitoring UEsthat are interested in these messages may read them and may processthem. In an example, this model may be equivalent to “I am here” sincethe announcing UE may broadcast information about itself e.g. itsrestricted ProSe application code in the discovery message.

The UE may act as “announcing UE” in the carrier frequency signaled bythe serving PLMN when using Model A mode. The UE may act as a“monitoring” UE in the resources of the serving PLMN and Local PLMNs,when using Model A mode. When inter-PLMN discovery transmission issupported, the carrier frequency may be operated by a PLMN other thanthe serving PLMN. Open and/or restricted discovery types may besupported by Model A.

Model B, when restricted discovery type is used, includes the followingexamples two roles for the ProSe-enabled UEs that are participating inProSe Direct Discovery: a) Discoverer UE: The UE transmits a requestcontaining certain information about what it is interested to discover.b) Discoveree UE: The UE that receives the request message may respondwith some information related to the discoverer's request.

In an example, it is equivalent to “who is there/are you there”. Thediscoverer UE sends information about other UEs that may like to receiveresponses from, e.g. the information may be about a ProSe applicationidentity corresponding to a group and the members of the group mayrespond.

When using Model B discovery, the discoverer UE and discoveree UE mayannounce in the carrier frequency signaled by the serving PLMN. Wheninter-PLMN discovery transmission is supported, the carrier frequencymay be operated by a PLMN other than the serving PLMN. The discoverer UEand discoveree UE may be allowed to monitor in the serving PLMN andLocal PLMNs when authorized. In an example implementation, onlyrestricted discovery type may support by Model B. In an exampleapplication, the public safety discovery may be considered restricted.The monitoring UE/discoverer UE may need to have authorization (such asthrough pre-provisioned parameters) to perform discovery of theappropriate service(s).

The public safety discovery is considered restricted and depending onModel A or Model B, it may use ProSe restricted code for Model A, it mayuse ProSe query code/ProSe response code respectively for Model B.

These code parameters may ben bits, e.g. 64 bits, and may be part ofProSe Application Code. They may correspond to one or more restrictedProSe application user ID(s) (RPAUID). The ProSe application user ID maybe allocated and bound to ProSe discovery UE ID (PDUID) by the ProSeapplication server.

FIG. 6 is an example of a ProSe Discovery message which may be employedfor discovery procedures in Model A and Model B. In Model A, theannouncing MCS UE may use ProSe restricted code and if theapplication-controlled extension is used, it may use ProSe restrictedcode prefix and ProSe restricted code suffix(es) to announce itsidentity over the PC5 interface. The monitoring MCS UE may use discoveryfilter which may be provided by the HPLMN ProSe function comprising theProSe restricted code (or ProSe restricted code prefix with ProSeRestricted Code suffix pool if restricted direct discovery withapplication-controlled extension was requested by the announcing MCS UE)to monitor the announcing MCS UE for a duration of time.

Model A may compromise a procedure for the announcing MCS UE and aprocedure for the monitoring MCS UE. It may include a matching procedurefor the case when the monitoring MCS UE receives ProSe restricted codeover the air that matches the discovery filter provided by the HPLMNProSe function to the monitoring MCS UE in the discovery responsemessage, however the corresponding restricted ProSe application UEidentity (RPAUID) does not have valid validity timer.

FIG. 7 is a flow diagram of an example procedure for Model A discovery.This example procedure for the Model A discovery may include one or moreof the following:

Authorization: The MCS UE may get authorized for restricted ProSe directdiscovery. In an example, MCS may be public safety and the ProSe directdiscovery may be restricted.

Announcement: The announcing MCS UE may request for discovery and mayreceive the ProSe restricted code (or ProSe restricted code prefix andProSe restricted code suffix(es) to announce itself, if theapplication-controlled extension is used). The announcing MCS UE mayannounce the ProSe restricted code (or ProSe restricted code prefix andProSe restricted code suffix(es) to announce itself, if theapplication-controlled extension is used).

Monitoring: The monitoring MCS UE may request for discovery and mayreceive the ProSe Filter comprising the ProSe Restricted Code (or ProSeRestricted Code Prefix and ProSe Restricted Code Suffix(es) to announceitself, if the application-controlled extension is used). The monitoringMCS UE may monitor for the ProSe restricted code (or ProSe restrictedcode prefix and ProSe restricted code suffix(es) to announce itself, ifthe application-controlled extension is used).

Match-Reporting: The monitoring UE may match-report if having monitoredProSe restricted code (or ProSe restricted code prefix and ProSerestricted code suffix(es) to announce itself, if theapplication-controlled extension is used) with corresponding PRAUID withno valid validity timer.

The announcing, monitoring, and match-reporting procedures are explainedbelow. FIG. 8, FIG. 9, and FIG. 10.

FIG. 8 is a flow diagram showing an example procedures for theannouncing MCS UE. An example procedure for the announcing MCS UE is asfollows:

The application client in the MCS UE may retrieve the ProSe discovery UEidentity (PDUID) and may provide it to the ProSe application server. TheProSe application server may allocate a restricted ProSe application UEidentity (RPAUID) for that PDUID, may store the binding between thePDUID and the RPAUID and may return the RPAUID to the application clientin the MCS UE. MCS UE may use RPAUID instead of PDUID since MCS is apublic safety feature.

MCS UE may construct a discovery request message containing RPAUID, UEidentity set to international mobile subscriber identity (IMSI),command=announce, discovery type set to restricted discovery,application ID set to unique identifier of the MCS application ID,discovery entry ID indicating if this is a new request, optionalrequested discovery timer set to validity timer associated with theexpected ProSe restricted code from the HPLMN ProSe Function (if it isset to zero, the MCS UE is requesting to remove the discovery entity IDand release the associated resources), (if application-controlledextension is used) application level container containing the requestand the relevant information, announcing type such as “on demand” forthe indicated application, and the PLMN ID of the carrier frequency inannouncing PLMN ID if the serving PLMN signaled carrier frequency is notoperated by HPLMN or VPLMN and if inter-PLMN ProSe discoverytransmission is supported. MCS UE may send the discovery request messageto HPLMN ProSe function.

HPLMN ProSe function may check for authorization for the MCSapplication. If there is not any associated MCS UE context, the HPLMNProSe function may check with HSS and if needed may create a new contextfor the MCS UE that contains the subscription parameters for this MCSUE. HSS may provide MSISDN of the MCS UE and PLMN ID of where the MCS UEis registered.

The HPLMN ProSe function may send an authorization request containingRPAUID and request type set to “restricted discovery/announce” towardsthe ProSe application server. The authorization request may containallowed number of suffixes if restricted Direct Discovery withapplication-controlled extension is used. The request type is set to“restricted discovery with application-controlled extension/announce”.

The ProSe application server may answer by an authorization responsecontaining PDUID(s) corresponding the RPAUID stored in the ProSeapplication server and response type set to “restricteddiscover/announce ack”. The authorization respond may include ProSerestricted code suffix pool with allocated suffixes by the ProSeApplication if restricted direct discovery with application-controlledextension is used. The response type is set to “restricted discoverywith application-controlled extension/announce ack”.

HPLMN ProSe function may assign a ProSe restricted code corresponding tothe RPAUID in the discovery request and an associated validity timerwhich identifies the duration of validity of the ProSe restricted code.MCS UE may use this ProSe restricted code within this validity durationif PLMN is not changed. If restricted direct discovery withapplication-controlled is used, then HPLMN ProSe functions may assignProSe restricted code prefix instead of ProSe restricted code. Ifdiscovery request message indicates “on demand” announcing and the “ondemand” announcing is authorized and enabled based on application ID andoperator's policy, the HPLMN ProSe function may store RPAUID, PreSerestricted code (or ProSe restricted code prefix) with the associatedvalidity timer, and enabled indicator in the user context. “On demand”announcing is only activated based on an ongoing monitoring request,otherwise, the following steps are not executed.

If the Discovery request is authorized, HPLMN ProSe Function mayconstruct announce authorization message containing RPAUID, MCSapplication ID, ProSe restricted code (or ProSe restricted code prefixwith ProSe restricted code suffix pool if restricted direct discoverywith application-controlled extension is used) set to assigned code forthis request, UE ID set to IMSI or mobile station identifier number(MSISDN), discovery entry ID, and validity timer. The HPLMN ProSefunction may update the existing announcing MCS UE's discovery entrywith the new ProSe restricted code (or the ProSe restricted code prefixwith ProSe restricted code suffix pool if restricted direct discoverywith application-controlled extension is used) and the new validitytimer by using the MCS UE's corresponding discovery entry ID included inthe discovery request message. If discovery request message includeddiscovery timer set to zero for a discovery entity ID, then the HPLMNProSe function may inform the VPLMN ProSe function to remove resourcesfor that discovery entry ID by setting the timer to zero. The HPLMNProSe function may send the announce authorization message towards theVPLMN ProSe Function.

The VPLMN ProSe function may acknowledge the HPLMN ProSe function thatit authorizes the MCS UE to perform restricted discovery announcing ifthe announce authorization message contain a new discovery entery ID. Ifthe discovery entery ID already exists, the VPLMN ProSe function mayacknowledge the update as requested.

If the announcing is not “on-demand”, the HPLMN ProSe function mayconstruct a discovery respond message with ProSe restricted code (orProSe restricted code prefix with ProSe restricted code suffix pool ifrestricted direct discovery with application-controlled extension isused), validity timer, and discovery entity ID. If the announcing is“on-demand” and is authorized and enabled, the HPLMN ProSe function mayconstruct the discovery respond message with validity timer, announcingenabled indicator, and discovery entity ID. The validity timer is set tozero if it is zero in discovery request message originated by the MCSUE. The HPLMN ProSe function may send the discovery respond messagetowards the MCS UE.

MCS UE may start announcing the provided ProSe restricted code. ifrestricted direct discovery with application-controlled extension isused, the MCS UE may append a ProSe restricted code suffix from thereceived ProSe restricted code suffix pool to the ProSe Restricted CodePrefix to form a ProSe Restricted Code. The MCS UE may use differentsuffixes from the provided ProSe restricted code suffix pool to form andannounce different ProSe restricted codes without having to contact theHPLMN ProSe function as long as the validity timer permits. If“on-demand” announcing is used and the HPLMN ProSe function has notprovided ProSe restricted code (or ProSe restricted code prefix withProSe restricted code suffix pool if restricted direct discovery withapplication-controlled extension is used), the MCS UE may need to waitfor an announcing alert request message from the HPLMN ProSe functionbefore announcing on PC5 interface.

FIG. 9 is a flow diagram showing an example procedures for themonitoring MCS UE. The example procedure for monitoring MCS UE is asfollows:

The application client in the MCS UE may retrieve the ProSe discovery UEidentity (PDUID) and may provide it to the ProSe application server. TheProSe application server may allocate a restricted ProSe application UEidentity (RPAUID) for that PDUID, may store the binding between thePDUID and the RPAUID and may return the RPAUID to the application clientin the MCS UE. The MCS UE may obtain RPAUIDs of those MCS target usersfrom the ProSe Application Server passed in an application levelcontainer. RPAUID instead of PDUID is used since MCS is a public safetyfeature.

In order to get the discovery filter, the monitoring MCS UE mayconstruct a discovery request message comprising RPAUID set to themonitoring MCS UE identity, UE identity set to IMSI, command=monitor,discovery type, application ID set to unique identifier for theapplication that triggered discovery procedure, application levelcontainer compromising the Target RPAUIDs that the MCS UE is to monitor,discovery entry ID showing the discovery identity that it is a newdiscovery or an existing one, and the optional requested discoverytimer. The requested discovery timer may be set to zero to indicateHPLMN to delete the discovery filter(s) for that discovery entry ID. Theapplication level container may include some information about ProSerestricted code suffix such as group or user specific information ifdirect discovery with application-controlled extension is used. The MCSUE may send the discovery request message towards HPLMN ProSe function.

HPLMN ProSe function may check for authorization for the MCSapplication. If there is not any associated MCS UE context, the HPLMNProSe function may check with HSS and if needed may create a new contextfor the MCS UE that contains the subscription parameters for this MCSUE. HSS provides also MSISDN of the MCS UE and PLMN ID of where the MCSUE is registered.

The HPLMN ProSe function may send an authorization request containingRPAUID and request type set to “restricted discovery/monitor” towardsthe ProSe application server. If restricted direct discovery withapplication-controlled extension is used, the request type is then setto “restricted discovery with application-controlled extension/monitor”.

The ProSe application server constructs an authorization responsecomprising target PDUIDs and corresponding Target RPAUID that the RPAUIDin the authorization request may monitor, PDUID of the requesting MCSUE, and response type set to “restricted discovery/monitor ack” (or to”restricted discovery with application-controlled extension/monitor ack”if restricted direct discovery with application-controlled extension isused). The ProSe application server may send the authorization responsetowards the HPLMN ProSe function.

The HPLMN ProSe function may construct a monitor request messagecomprising RPAUID of monitoring MCS UE, UE identity set to IMSI orMSISDN, Target PDUID and corresponding target RPAUID, application ID setto unique identifier for application that triggered the discoveryprocedure, and discovery entry ID to identify the discovery entry beingnew or an existing one. The HPLMN ProSe function may send the monitorrequest towards the target PLMN ProSe function which belongs to themonitoring MCS UE. If the discovery entry ID is an existing one, thetarget PLMN ProSe function may modify the existing discovery procedurewith the parameters included in the monitor request message.

The target PLMN ProSe function may retrieve the ProSe restricted code(or the ProSe restricted code prefix if the restricted direct discoverywith application-controlled extension is used) corresponding to thetargeted PDUID, targeted RPAUID, and application ID. If in the contextof the announcing MCS UE, the announcing enabled indicator is stored,the target PLMN ProSe function may construct an announcing alert requestmessage comprising RPAUID indicating which monitoring MCS UE isinterested in the targeted MCS UE announcement, application ID set tounique identifier for the application that triggered discoveryprocedure, ProSe restricted code which was retrieved from the context ofthe targeted announcing MCS UE (or ProSe restricted code prefix withProSe restricted code suffix pool if restricted direct discovery withapplication-controlled extension was requested by the announcing MCSUE), and discovery entry ID to indicate it is a new discovery entity oran existing one. The target PLMN PRoSe function may send the messagetowards the targeted MCS UE and upon receipt of the announce alertresponse message from that MCS announcing UE, the ProSe function removesthe announcing enabled indication associated to the ProSe restrictedcode (or ProSe restricted code prefix with ProSe restricted code suffixpool if restricted direct discovery with application-controlledextension was requested by the announcing MCS UE) from the AnnouncingMCS UE context. The MCS UE may now start announcing the ProSe restrictedcode (or ProSe restricted code prefix with ProSe restricted code suffixpool if restricted direct discovery with application-controlledextension was requested by the announcing MCS UE).

The target ProSe function may construct an authorization request messagecomprising RPAUID set to that of the monitoring MCS UE, Request Type setto “restricted discovery/permission”, and target RPAUID set to that ofthe announcing MCS UE. The target ProSe function may send theauthorization request message towards the ProSe application server.

The ProSe application server may acknowledge the target ProSe functionby constructing an authorization response message comprising PDUID ofthe announcing MCS UE which is to be monitored and response type set to“restricted discovery/permission ack” and by sending it towards thetarget PLMN ProSe function.

The target ProSe function constructs a monitor response messagecompromising ProSe restricted code (or ProSe restricted code prefix withProSe restricted code suffix pool if restricted direct discovery withapplication-controlled extension was requested by the announcing MCS UE)and the corresponding validity timer. The target ProSe function may sendthe monitor response message towards the HPLMN ProSe function.

From the ProSe application server, the HPLMN ProSe function has nowretrieved the ProSe restricted code (or ProSe restricted code prefixwith ProSe restricted code suffix pool if restricted direct discoverywith application-controlled extension was requested by the announcingMCS UE) and the corresponding validity timer for each pair of targetPDUID-target RPAUID bound with application ID and stored as the usercontent of the monitoring MCS UE. The HPLMN ProSe function based on theProSe restricted code (or ProSe restricted code prefix with ProSerestricted code suffix pool if restricted direct discovery withapplication-controlled extension was requested by the announcing MCS UE)and the corresponding validity timer, allocates a discovery filter withcorresponding time-to-live (TTL).

The HPLMN ProSe function may construct a discovery response messagecomprising target RPAUID(s) and the corresponding discovery filter(s)that comprises ProSe restricted code (or ProSe restricted code prefixwith ProSe restricted code suffix pool if restricted direct discoverywith application-controlled extension was requested by the announcingMCS UE) to be monitored and the corresponding TTL showing how long thefilter is valid. If the requested discovery timer in discovery requestmessage sent by MCS monitoring UE was set to zero, the TTL in thediscovery response message is set to zero. The discovery responsemessage also comprises discovery entry ID to identify the discoveryentity. The HPLMN ProSe function may send the discovery response messagetowards the monitoring MCS UE.

The MCS UE uses the discovery filter to monitor the announcing MCS UE.

FIG. 10 is a flow diagram showing an example match reporting procedure.The example procedure for match reporting for announcing/monitoring isas follows:

If the monitoring MCS UE has over the air received a ProSe restrictedcode (or the ProSe restricted code prefix and the ProSe restricted codesuffix if the restricted direct discovery with application-controlledextension is used) is matching the discovery filter obtained in thediscovery response message from the HPLMN ProSe function but theannouncing MCS UE does not have an RPAUID with a valid TTL, themonitoring MCS UE may construct a match report message comprising itsown RPAUID, its IMSI or MSISDN as UE identity, discovery type set to“restricted discovery”, application ID set to unique identifier for theapplication that triggered the monitoring request, the over the airreceived ProSe restricted code, optional metadata requested, andannouncing PLMN ID of the PLMN where the announcing MCS UE wasmonitored. The monitoring MCS UE transmits the match report messagetowards the HPLMN ProSe function.

The HPLMN ProSe function may verify if the monitoring MCS UE may performrestricted discovery and may analyze ProSe restricted code (or the ProSerestricted code prefix and the ProSe restricted code suffix if therestricted direct discovery with application-controlled extension isused). The HPLMN ProSe function may identify the announcing MCS UE'sRPAUID in the context of the monitoring MCS UE.

If metadata requested was included to the originated match reportmessage by the monitoring MCS UE, the HPLMN ProSe function may locatethe ProSe application server from the application ID and may constructan authorization request message comprising monitoring MCS UE's RPAUID,announcing MCS UE's RPAUID, and request type set to “restricteddiscovery/match”. The HPLMN ProSe function may send the authorizationrequest message towards the ProSe application server. This step isoptional if metadata requested was not included into the original matchreport message.

The ProSe application server may construct an authorization responsecomprising monitoring MCS UE's PDUID, announcing MCS UE's PDUID,response type set to “restricted discovery/match ack”, and metadatacorresponding to the Announcing MCS UE.

The HPLMN ProSe function may verify that the PDUID belongs to themonitoring MCS UE and the announcing MCS UE's PDUID are the same as theannouncing MCS UE's PDUID that is stored in the context of theMonitoring MCS UE.

The HPLMN ProSe function may construct a match report ack comprisingapplication ID set to unique identifier for the application thattriggered the monitoring request, announcing MCS UE's RPAUID, validitytimer, and optionally meta data.

The monitoring MCS UE may store the mapping between the ProSe restrictedcode (or the ProSe restricted code prefix and the ProSe restricted codesuffix if the restricted direct discovery with application-controlledextension is used), announcing MCS UE's PRAUID, the application IDunique identifier of the application that triggered the monitoringprocedure, and the related validity timer.

The HPLMN ProSe function may construct a Mach Report Info messagecomprising Monitoring MCS UE's RPAUID, announcing MCS UE's RPAUID,announcing MCS UE's identity set to IMSI or MSISDN for chargingpurposes, ProSe restricted code (or the ProSe restricted code prefix andthe ProSe restricted code suffix if the restricted direct discovery withapplication-controlled extension is used), and discovery type set to“restricted discovery”. The HPLMN ProSe function may send the matchreport info message towards the announcing MCS UE's PLMN ProSe functionand the ProSe function of the PLMN where the announcing MCS UE may beroaming in.

In Model B, the discoverer MCS UE may use ProSe query code to find thediscoveree MCS UE. The discoveree MCS UE may use ProSe response code toidentify itself. The ProSe response code is sent by the discoveree MCSUE over the air upon receiving a ProSe query code matching any discoveryquery filter(s). The discoverer MCS UE discovers then the discoveree MCSUE by matching the ProSe response code to any discovery responsefilter(s). The ProSe query code, and the discovery response filter(s)are allocated by HPLMN ProSe function to the discoverer MCS UE. TheProSe response code and discovery query filter(s) are allocated by theHPLMN ProSe function to the discoveree MCS UE.

Model B compromises procedure for the discoveree MCS UE and procedurefor the discoverer MCS UE procedure. It may include matching procedurefor the case when the discoverer MCS UE receives ProSe response codeover the air that matches the discovery filter provided by the HPLMNProSe function to the discoveree MCS UE in the discovery responsemessage, however the corresponding RPAUID does not have valid validitytimer. Model B is always for restricted discovery.

FIG. 11 is a flow diagram showing an example procedures for Model Bdiscovery. The example procedure for the Model B discovery is asfollows:

Authorization: The MCS UE may get authorized for restricted ProSe directdiscovery. In an example, MCS may be public safety and the ProSe directdiscovery may be restricted.

Discoveree procedure: The discoveree MCS UE may request for discoveryand may receive the ProSe response code and associated discovery queryfilter(s). The discoveree MCS UE may employ the discovery filter(s) tomonitor ProSe query code on PC5. The discoveree MCS UE may announce theProSe response code if receiving a ProSe query code over the air whichmatches any of discovery filter(s).

Discoverer procedure: The discoverer MCS UE may request for discoveryand may receive the ProSe query code and associated discovery responsefilter(s). The discoverer MCS UE may announce the ProSe query code onPC5 interface. The discoverer MCS UE may monitor ProSe response code onPC5 interface that may match any of the discovery response filter(s).The discoverer UE may match-report if having discovered ProSe responsecode with corresponding PRAUID with no valid validity timer.

Example discoveree, discoverer, and match-reporting procedures areexplained below with respect to FIG. 12, FIG. 13, and FIG. 14. FIG. 12is a flow diagram showing an example procedure for the discoveree MCSUE. The example procedure for discoveree MCS UE is as follows:

The application client in the MCS UE may retrieve the ProSe discovery UEidentity (PDUID) and may provide it to the ProSe application server. TheProSe application server may allocate a restricted ProSe application UEidentity (RPAUID) for that PDUID, may store the binding between thePDUID and the RPAUID and may return the RPAUID to the application clientin the MCS UE. The application client in the MCS UE may store thebinding between the RPAUID and its own PDUID and may use those RPAUID toperform discoveree request procedure.

The discoveree MCS UE may establish connection to HPLMN ProSe functionand may construct a discovery request message comprising RPAUID set towhat the MCS UE will announce, UE identity set to IMSI, commandindicating this is for discoveree UE, discovery type set to “restricteddiscovery”, discovery model indicating Model B, application ID set tounique identifier for the application that triggered discoveryprocedure, discovery entry ID showing the discovery identity that it isa new discovery or an existing one, and PLMN ID of the carrier frequencyin announcing PLMN ID if the serving PLMN signaled carrier frequency isnot operated by HPLMN or VPLMN and if inter-PLMN ProSe discoverytransmission is supported. MCS UE may send the discovery request messageto HPLMN ProSe function.

HPLMN ProSe function may check for authorization for the MCSapplication. If there is not any associated MCS UE context, the HPLMNProSe function may check with HSS and if needed may create a new contextfor the MCS UE that contains the subscription parameters for this MCSUE. HSS may provide MSISDN of the MCS UE and PLMN ID of where the MCS UEis registered.

The HPLMN ProSe function may locate the ProSe application server basedon the application ID in the discovery request message and may send anauthorization request containing RPAUID and request type set to“restricted discovery/response” towards the ProSe application server.

The ProSe application server may answer by an authorization responsecontaining PDUID(s) corresponding the RPAUID stored in the ProSeapplication server and response type set to “restricteddiscover/response ack”.

The HPLMN ProSe function may verify that at least of one of the PDUID(s)may belong to the discovree MCS UE. The HPLMN ProSe function may assigna ProSe response code and ProSe query code with the associated discoveryquery filter(s). The ProSe response code corresponds to the RPAUID inthe discovery request and the HPLMN ProSe function may assign anassociated validity timer for the ProSe response code and ProSe querycode with the associated discovery query filter(s). The validity timeridentifies the duration of validity of the ProSe response code and ProSequery code with the associated discovery query filter(s). The discovereeMCS UE may use this ProSe response code within this validity duration ifPLMN is not changed. The HPLMN ProSe function may store ProSe responsecode with its associated validity timer and ProSe query code withassociated discovery query filter(s) in the context of the MCS user.

If the discovery request is authorized, HPLMN ProSe function mayconstruct announce authorization message containing RPAUID, MCSapplication ID, ProSe response set to assigned code for this request, UEID set to IMSI or MSISDN, discovery entry ID to identify the discoveryentry, and validity timer indicating how long the ProSe response codewill be valid. The HPLMN ProSe function may send the announceauthorization message towards the VPLMN ProSe function.

The VPLMN ProSe function may acknowledge the HPLMN ProSe function thatit authorizes the MCS UE to perform restricted discovery announcing ifthe announce authorization message contain a new discovery entry ID. Ifthe discovery entry ID already exists, the VPLMN ProSe function mayacknowledge the update as requested i.e. updating the discoveree MCSUE's discovery entry by the new ProSe response code and its associatedvalidity timer.

The HPLMN ProSe function may construct a discovery response message withdiscovery type set to Model B, ProSe response code, discovery queryfilter(s) suited for certain ProSe Query code, validity timer associatedto ProSe response code and the discovery query filter(s), and discoveryentity ID to identify the discovery identity. The MCS discoveree UE mayuse the discovery query filter(s) (which may be multiple) to determinewhich ProSe query code triggers that the MCS discoveree UE announces theassigned ProSe response code. The HPLMN ProSe function may send thediscovery response message towards MCS discoveree UE.

The MCS discoveree UE may use the discovery query filter(s) which manybe multiple to determine which ProSe query code triggers that the MCSdiscoveree UE announces the assigned ProSe response code. If thevalidity timer expires, the MCS discoveree ue may send a new discoveryrequest message towards the HPLMN ProSe function.

FIG. 13 is a flow diagram of an example procedure. The procedure fordiscoverer MCS UE is as follows:

The application client in the MCS UE may retrieve the ProSe discovery UEidentity (PDUID) and may provide it to the ProSe application server. TheProSe application server allocates a restricted ProSe application UEidentity (RPAUID) for that PDUID, may store the binding between thePDUID and the RPAUID and may return the RPAUID to the application clientin the MCS UE. The MCS UE may obtain RPAUIDs of those MCS target usersfrom the ProSe application server passed in an application levelcontainer. RPAUID instead of PDUID may be used for public safety featureMCS.

The discoverer MCS UE may establish connection to the MPLMN ProSefunction and may construct a discovery request message comprising RPAUIDset to what the discoverer MCS UE wants to announce, UE identity set toIMSI, command showing this is for ProSe query procedure, discovery typeset to “restricted discover”, discovery model set to Model B,application ID set to unique identifier for the application thattriggered discovery procedure, application level container compromisingthe target RPAUIDs that the MCS UE is to discover, discovery entry IDshowing the discovery identity that it is a new discovery or an existingone, and the optional requested discovery timer. The requested discoverytimer is set to zero to indicate HPLMN to delete the discovery filter(s)for that discovery entry ID. The MCS UE may send the discovery requestmessage towards HPLMN ProSe Function.

HPLMN ProSe function may check for authorization for the MCSapplication. If there is not any associated MCS UE context, the HPLMNProSe function may check with HSS and if needed may create a new contextfor the MCS UE that contains the subscription parameters for this MCSUE. HSS may provide MSISDN of the MCS UE and PLMN ID of where the MCS UEis registered.

The HPLMN ProSe function may locate the ProSe application server basedon the application ID in the discovery request message and may send anauthorization request containing RPAUID, request type set to “restricteddiscovery/query”, and application level container towards the ProSeapplication server.

The ProSe application server may construct an authorization responsecomprising target PDUIDs and corresponding target RPAUID that the RPAUIDin the authorization request may discover, PDUID of the requesting MCSUE, and response type set to “restricted discovery/query ack”. The ProSeapplication server may send the authorization response towards the HPLMNProSe function.

The HPLMN ProSe function may allocate the context for the discovereeUE(s) if the PLMN ID in the target PDUID-target RPAUID corresponds to avalid ProSe response code. The HPLMN ProSe function may allocate thediscovery response filter(s) which trigger the MCS discoveree UE totransmit the ProSe response code. This procedure has expiration timewhich is specified by validity timer.

The HPLMN ProSe function may construct a discovery request messagecomprising RPAUID of discoveree MCS UE, UE identity set to IMSI orMSISDN, target PDUID and corresponding target RPAUID, application ID setto unique identifier for application that triggered the discoveryprocedure, and discovery entry ID to identify the discovery entry beingnew or an existing one. The HPLMN ProSe function may send the discoveryrequest towards the target PLMN ProSe Function which belongs to thediscoveree MCS UE. If the discovery entry ID is an existing one, theTarget PLMN ProSe function may modify the existing discovery procedurewith the parameters included in the discovery request message.

The target ProSe Function has an option to construct an authorizationrequest message comprising RPAUID set to that of the discoverer MCS UE,Request Type set to “restricted discovery/query”, and target RPAUID setto that of the discoveree MCS UE. The target ProSe function may send theauthorization request message towards the ProSe application server.

The ProSe application server may acknowledge the target ProSe functionby constructing an authorization response message comprising PDUID ofthe discovery MCS UE, response type set to “restricted discovery/queryack”, and target PDUID of the discoveree MCS UE. The ProSe applicationserver may send the authorization response message towards the targetPLMN ProSe function.

The target PLMN ProSe function may allocate the context of thediscoveree MCS UE based on target PDUEID-target RPAUID and theapplication ID. The target PLMN ProSe function may respond with adiscovery response comprising ProSe query code which will be used byHPLMN ProSe function to build the discovery query filter so that ittriggers the discoveree UE to send ProSe Response code, the actual ProSeresponse code, and validity timer to indicate for how long the ProSeQuery code and ProSe response code are valid.

The HPLMN ProSe function may construct an announce authorization messagecomprising RPAUID of the discovery MCS UE, application ID, ProSe querycode and its associated validity timer, UE identity set to IMSI orMSISDN of discovery MCS UE for charging purposes in the visiting domain,and discovery entry ID to identify the discovery entry. The HPLMN ProSefunction may send the announce authorization message towards the VPLMNProSe function.

The VPLMN may acknowledge that it authorizes the discovery MCS UE toperform ProSe direct discovery procedure. If the discovery entry ID inthe announce authorization message corresponded an already discoveryentry, the VPLMN ProSe function may acknowledge the replacement of theexisting ProSe query code and its associated validity timer.

The HPLMN ProSe function may construct the discovery response messagecomprising discovery model set to Model B, ProSe query code, one ormultiple discovery response filters which are generated by the HPLMNProSe function based on ProSe response code, and validity timer for howlong the ProSe query code and discovery response filter(s) are valid.The HPLMN ProSe Function may transmit the Discovery Response message tothe Discoverer MCS UE.

The discoverer MCS UE may obtain the information from the discoveryresponse message to discover discoveree MCS UE. If the validity timer isexpired, the discoverer MCS UE may send a new discovery request messagetowards the HPLMN ProSe function.

FIG. 14 is a flow diagram showing an example matched reportingprocedure. An example procedure for match reporting fordiscoveree/discoverer is as follows:

If the discoverer MCS UE may have received over the air a ProSe responsecode is matching the discovery response filter obtained in the discoveryresponse message from the HPLMN ProSe function but the discoveree MCS UEdoes not have an RPAUID with a valid TTL, the discoverer MCS UE mayconstruct a match report message comprising its own RPAUID, its IMSI orMSISDN as UE Identity, discovery type set to “restricted discovery”,application ID set to unique identifier for the application thattriggered the monitoring request, the over the air received ProSeresponse code, optional metadata requested, and discoveree PLMN ID ofthe PLMN where the discoveree MCS UE was discovered. The discoveree MCSUE may transmit the match report message towards the HPLMN ProSeFunction.

The HPLMN ProSe function may verify if the discoverer MCS UE hasperformed restricted discovery and may analyze Prose response code. TheHPLMN ProSe function may identify the discoveree MCS UE's RPAUID in thecontext of the discoverer MCS UE.

If metadata requested was included to the originated match reportmessage by the discoverer MCS UE, the HPLMN ProSe function may locatethe ProSe application server from the application ID and may constructan authorization request message comprising discoverer MCS UE's RPAUID,discoveree MCS UE's RPAUID, and request type set to “restricteddiscovery/match”. The HPLMN ProSe function may send the authorizationrequest message towards the ProSe application server. This step isoptional if metadata requested was not included into the original matchreport message.

The ProSe application server may construct an authorization responsecomprising discoverer MCS UE's PDUID, discoveree MCS UE's PDUID,response type set to “restricted discovery/match ack”, and metadatacorresponding to the discoveree MCS UE.

The HPLMN ProSe function may verify that the PDUID belongs to thediscoverer MCS UE and the discoveree MCS UE's PDUID are the same as thediscoveree MCS UE's PDUID that is stored in the context of thediscoverer MCS UE.

The HPLMN ProSe function may construct a match report ack comprisingapplication ID set to unique identifier for the application thattriggered the discovery request, discoveree MCS UE's RPAUID, validitytimer, and optionally meta data.

The discoverer MCS UE may store the mapping between the ProSe responsecode, discoveree MCS UE's PRAUID, the application ID unique identifierof the application that triggered the discovery procedure, and therelated validity timer.

The HPLMN ProSe Function may construct a match report info messagecomprising discoverer MCS UE's RPAUID, discoveree MCS UE's RPAUID,discoveree MCS UE's Identity set to IMSI or MSISDN for chargingpurposes, ProSe response code, and discovery type set to “restricteddiscovery”. The HPLMN ProSe function may send the match report infomessage towards the discoveree MCS UE's PLMN ProSe function and theProSe function of the PLMN where the discoveree MCS UE may be roamingin.

FIG. 15 is a block diagram of an example MCS UE-to-network relay. Apublic safety ProSe (MCS) UE may provide the functionality to supportconnectivity to the network for a remote MCS UE. An MCS UE is consideredto be remote if it has established a successful PC5 link connection to aUE-to-Network relay. A remote MCS UE may be out of E-UTRAN coverage. AnMCS UE may be within a coverage of E-UTRAN and may choose not to useE-UTRAN coverage. At the time of discovery ProSe relay service codes forMCS services in the MCS UE-to-Network relay are recognized by the remoteMCS UE to identify the MCS UE-to-Network relay. Relay service codes arepre-provisioned in the MCS UE-to-Network relay and the remote MCS UE andare communicated by discovery announcement message for Model A ProSediscovery and by discovery solicitation message/discovery responsemessage for Model B ProSe discovery. The remote MCS UE employs the MCSUE-to-Network relay to access E-UTRAN and thereby performing IMSregistration and also MCS session establishment.

The MCS UE-to-Network relay may function as a relay for unicast trafficbetween remote UE and the network by relaying any IP traffic to the UE.The MCS UE-to-Network relay may function as a relay for multicastbroadband multicast service (MBMS) traffic using one ProSe DirectCommunication.

In this context, the MCS UE may be represented by a remote MCS UE and aUE-to-Network MCS UE which have PC5 interface to each other. This may betransparent to the E-UTRAN network and/or IMS network.

To set up an on-network MCS media session, the MCS UEs may register withIP Multimedia Subsystem (IMS) network. At the time of registration tothe IMS network, an MCS UE may register its supported IMS communicationservice it intends to use. The MCS UE may also register its supportedIMS applications it intends to use at the time of IMS registration. TheIMS maintain the information the UE's capabilities for the possiblesession setup by a third party entity or another MCS UE. A third partyentity may like to get a MCS UE's capabilities from the operator'snetwork where MCS UE has registered to, in order to e.g. provide aservice or application. A third party entity may transmit a sessioninitiation protocol (SIP) message (e.g. SIP INVITE request) to the UE toset up a session. Therefore, the network must know the MCS UE'scapabilities to provide this information to the third party entity.

FIG. 16 is a flow diagram showing an example IMS registration procedureof an MCS UE. This example flow diagram shows: MCS UE may send a SIPREGISTER request containing MCS feature tag in contact header fieldtowards the P-CSCF in the visiting network. P-CSCF may use the MCS UE'sID to locate the I-CSCF in the home network by DNS query. I-CSCF in thehome network may select suitable S-CSCF with help of HSS. S-CSCF maychallenge the registration by requesting an authentication. If theauthentication information is not valid, S-CSCF may get it from HSS. MCSUE may provide authentication response and may send the SIP REGISTERrequest containing authentication response and the MCS feature tag inthe contact header towards the P-CSCF in the visiting network. P-CSCFmay use the MCS UE's ID to locate the I-CSCF in the home network by DNSquery. I-CSCF in the home network may select suitable S-CSCF with helpof HSS. S-CSCF may authenticate the MCS UE and may send registrationnotification to the HSS and may receive the MCS user profile from theHSS. The MCS user profile may be used for the 3rd party register to theMCS application server (AS). S-CSCF may respond to OK to the MCS UE.

FIG. 17 is a flow diagram of an example IMS registration of an MCS UE.MCS UE may register its supported IMS communication services and IMSapplications, it may intent to use to its contact header field of theregister message when registering to the IMS network. IMS network maylocate the most suitable S-CSCF for this registration and may forwardthe registration request to that S-CSCF. S-CSCF may challenge the MCS UEby sending authentication request to the UE. MCS UE may respond to theauthentication request. S-CSCF 3rd part may register the UE to the MCSAS.

New Dialog or Standalone Transaction: Once the MCS UEs are allregistered to the IMS network and if an MCS UE may like to establish anMCS media session, the MCS UE may declare all its supported IMScommunication services and all it supported IMS applications it intendsto use. If this is a request for a new dialog, a SIP header field may bepopulated comprising a public GRUU value, a temporary GRUU value, or SIPURI containing the contact address of the MCS UE; an “ob” SIP URIparameter; an indicator for IMS communication service that the MCS UEmay include in media feature tag; and an indicator for IMS applicationthat the MCS UE may include in a media feature tag.

The MCS UE may modify the established dialog capabilities by e.g. addinga media or requesting a supplementary service if the modification isdefined for the IMS communication service. If the modification is notdefined for that IMS communication service, the MCS UE may initiate anew dialog.

FIG. 18 is a flow diagram shows an example MCS group session setup byMCS UE. MCS UE 1 may initiate an MCS group session with MCS UE 2 and MCSUE 3 by sending an SIP INVITE request which may comprise MCS feature tagin a SIP header field. The SIP header field may also comprise the MCSfeature tag which may indicate that MCS service may be required for theMCS group session. IMS may validate the service profile of the MCS UE 1and may evaluate the filter criteria. It may thereafter forward theinvite towards MCS AS. MCS AS may accept the MCS group session and mayinvite MCS UE 2 and MCS UE 3 by sending an SIP INVITE request which maycomprise MCS feature tag in the SIP header field. The SIP header fieldmay also comprise the MCS feature tag which may indicate that MCSservice may be required for the MCS group session. HSS may be queried tolocate MCS UE 2 and MCS UE 3 and IMS may validate their service profileand may evaluate the filter criteria. MCS UE 2 and MCS UE 3 may acceptthe invitation for the MCS group session. IMS may notify the MCS UEsthat other MCS UEs have now joined the on-network MCS group session.

FIG. 19 is a flow diagram of an example MCS session setup by MCS UE A.MCS UE 1 may initiate an MCS session with other MCS UEs by sending anSIP INVITE request which may comprise MCS related IMS communicationservice and IMS application in the SIP header field. IMS may validatethe service profile of the MCS UE 1 and may locate the suitable S-CSCFto process the MCS session invitation. S-CSCF may forward the invitationto the MCS AS which may generate separate invitations towards other MCSUEs who were originally invited by MCS UE 1. The invited MCS UEs mayanalyze the capabilities of MCS UE 1 who invited them to the MCS sessionand may make decision to join the MCS session based on the requestedcapabilities by MCS UE 1. IMS may notify MCS UEs that other MCS UEs havejoined the MCS group session and the on-network MCS group session is nowestablished.

Example embodiments of mission critical push-to-talk (MCPTT) describemechanisms for handling group and/or organization affiliation of anMCPTT user to MCPTT groups and/or organizations. MCPTT is an example ofMCS. The disclosed embodiments for MCPTT may also be implemented in PTT(push to talk) type calls. In the disclosed embodiment, PTT may beconsidered as an example of a MCPTT type call. A non-limiting examplecontext in which the embodiments may be implemented is 3GPP MCPTTstandards. Some or more of the features described in the standards maybe implemented and some others may be optional and may not beimplemented in example embodiments.

One of the more of the following features may be features for on-networkand/or off-network MCPTT. An MCPTT user may be able to affiliate with amultiplicity of MCPTT groups, subject to restrictions configured by theMCPTT administrator. An MCPTT User with limited speaker resources (e.g.,a handheld UE) might find that playing out concurrent receivedaudio/data/media from multiple active MCPTT groups becomes confusing andmay also cause undesired voice/data/media distortion for the receivinguser. During periods of time when the MCPTT user is receiving audio frommultiple MCPTT groups, which MCPTT group's audio is presented to theMCPTT user is determined by the MCPTT user's choice, the priorityassociated with the talker of the selected MCPTT group(s), otherconsiderations or combinations of these. The MCPTT UE may be aware ofthe active groups to which the MCPTT user has affiliated or selected andthe identity of the other active receiving groups is available fordisplay on the MCPTT UE. When the receive activity from the SelectedMCPTT group stops, the MCPTT UE may present the audio from the nextgroup per the MCPTT user's choice or by other means.

The MCPTT service may provide that if there is an MCPTT emergency groupcall on one of the MCPTT groups that an MCPTT user is affiliated to, butthat user is already in a lower priority MCPTT group call or privatecall (with floor control), that the MCPTT user automatically hears theMCPTT emergency group call. Depending on the MCPTT User's settingsand/or the MCPTT UE capability the above feature may imply that theMCPTT user stops receiving from another MCPTT group (which may normallyhave a higher priority) or a private call (with floor control).

One or more of the following features may apply to on-network MCPTT. Inan example, some of these features may also implemented in anoff-network MCPTT. The MCPTT service may provide the user ID, associateduser ID alias(es), group ID, group aliases and, if available, theidentity of the mission critical organization name of the transmittingparticipant to the receiving MCPTT UEs unless the transmittingparticipant's identity is restricted. The MCPTT service may provide theuser ID and/or associated aliases, the identity of the selected MCPTTgroup, and, if available, the identity of the mission criticalorganization name of the transmitting MCPTT user to MCPTT UEs that arereceiving for display by each MCPTT UE.

In an example embodiment, the features may include one or more of thefollowing. An MCPTT UE operating off the network may be capable oftransmitting the user ID, alias(es), off-network MCPTT group and, ifavailable, mission critical organization name of the user who is talking(i.e., whose UE is transmitting) to all other users in the callincluding MCPTT UEs operating off the network that enter the call late.

In an example road accident case, an MCPTT user may be involved in groupcalls from several MCPTT groups such as police department, firedepartment, and critical medical department. The MCPTT user may benotified if a higher priority call is held by a group that the MCPTTuser is most affiliated with. For instance, if a fire fighter who isaffiliated with the above three MCPTT groups at a time of the roadaccident, receives a call from the fire department, the fire fighter maybe able to be interrupted by fire department in case of an emergency.Thus, it is necessary for the MCPTT users to be aware of other MCPTTusers' identities, group identities, and organization identities.

In an example embodiment, MCPTT users within an MCPTT group call mayneed to be aware of the user-ID, group-ID and/or organization ID of theMCPTT user who is the current talker (e.g. the user that is talking,sending data, and/or media). During the discovery, the MCPTT user may bepermitted to discover MCPTT users from the affiliated MCPTT groups. Theinformation about the other MCPTT user ID, group ID and organization IDmay not be provided from the discovery procedure. In the on-networkMCPTT case, this may be resolved by network engagement in the MCPTT callsetup.

In the case when an MCPTT user is engaged in several affiliated groupcalls in an on-network MCPTT call, the MCPTT group call administratormay handle the engagement of the MCPTT user in different affiliatedMCPTT group calls. If an audio media needs to be interrupted to passanother audio media, the MCPTT group call administrator may handle thatdue to the e.g. agreed rules and/or policies for MCPTT affiliated groupcalls.

FIG. 20 is a flow diagram illustrating an example call flow showingMCPTT UE 1 engaged in two different MCPTT affiliated group calls withMCPTT UE 2 and MCPTT UE 3. In this scenario, MCPTT UE 1 may receivemedia from both affiliated groups while may transmit to one. The MCPTTService may allow an MCPTT UE to be receiving or transmitting in oneMCPTT group while simultaneously receiving additional MCPTT Groups.

If the MCPTT group call administrator detects an incoming high priorityMCPTT group call from MCPTT UE 2 which has close affiliation with MCPTTUE 1, network administrator may suspend the MCPTT group call.Subsequently, the MCPTT UE 1 and MCPTT UE 2 may be in a media exchange.

Example embodiments disclose a mechanism for off-network MCPTT groupcall set up. In the case of off-network MCPTT, there is not any networkinvolvement in the MCPTT group calls and there is no centralized callcontrol. The call control may be handled in the MCPTT UEs. MCPTT UEs mayhave capabilities to inform the MCPTT user about the MCPTT user and itsaffiliated MCPTT groups and organizations.

MCPTT may employ ProSe discovery mechanism. The announced Temp ID may bespecific to MCPTT feature. There may be two models for discovery inProSe discovery procedures; Model A where the announced Temp IDcomprises ProSe Restricted Code and Model B where the announced Temp IDcomprises ProSe Query Code or ProSe Response Code. In an example, thelength of the announced Temp ID is 160 bits and it may comprise currentinformation about the MCPTT group ID and MCPTT user ID which may besubtracted from ProSe Restricted Code, ProSe Query Code, and ProSeResponse Code.

In an example embodiment, the announced Temp ID may comprise informationfields about the MCPTT users. The information fields may comprise atleast one of user ID, group ID, and/or organization IDs. At the time ofdiscovery, the discoverer may locally register the information about thediscoverees in terms of user ID, group ID, and organization IDs.

FIG. 21 is an example flow diagram showing that MCPTT UE 1, MCPTT UE 2,and MCPTT UE 3 have discovered each other and thereby, they are aware ofeach other's user ID, group ID, and organization ID. MCPTT UE 1 isengaged in separate MCPTT group calls with MCPTT UE 2 and MCPTT UE 3.MCPTT UE 1 may receive media from both affiliated groups while maytransmit to only one MCPTT UE. The MCPTT service may allow an MCPTT UEto receive or transmit in one MCPTT group while simultaneously receiveadditional MCPTT groups.

MCPTT UE 1 which has closer affiliation with MCPTT UE 2 receivesindication from MCPTT UE 2 about a high priority MCPTT group call. MCPTTUE 1 suspends the other MCPTT group call. Subsequently, MCPTT UE1 andMCPTT UE 2 may exchanging media.

In an example embodiment, the organization ids may be pre-provisioned inthe UEs or may be communicated to UEs via a network server such asOMA-DM, or other types of configuration/management server. In anexample, the organization ids may be pre-provisioned by a ProSe functionnetwork entity (e.g. a server). The ProSe function may transmit one ormore message to a UE. The one or more message may comprise theorganization IDs along with other parameters.

In an example embodiment, at least one floor control message may beemployed to communicate an organization ID of a user.

The floor control signaling is broadcasted within an off-network MCPTTgroup call, and a user who is engaged with several group calls mayreceive floor control messages from the other members belonging to thosegroups. Example embodiments enable the user to recognize a high prioritycall request from a specific group organization.

In an example, the floor control message may comprise the informationabout the user ID, group ID, and/or organization ID that user belongs.FIG. 22 is an example flow diagram showing MCPTT UE 1 engaged inseparate MCPTT group calls with MCPTT UE 2 and MCPTT UE 3. MCPTT UE 1may receive media from both affiliated groups while may transmit to one.The MCPTT service may allow an MCPTT UE to be receiving or transmittingin one MCPTT group while simultaneously receiving additional MCPTTgroups.

MCPTT UE 2 may construct a floor request message with a high priorityand may target to MCPTT UE1. Upon receipt of the floor request messageMCPTT UE 1 may find out about the request's priority and the MCPTT UE 2organization from SSRC. MCPTT UE 1 has closer affiliation with MCPTT UE2 than the one with MCPTT UE 3 and therefore suspends the MCPTT groupcall with MCPTT UE 3. MCPTT UE1 and MCPTT UE 2 are now exchanging media.

FIG. 23A is a diagram of an example floor control message tagged with anassociated organization value. The example message may comprise theinformation about user ID and group ID. In an example, the followingformat may be implemented including e.g. an optional parameter,Organization value. FIG. 23B is a diagram of an example floor controlmessages comprising an optional parameter, Organization value.

FIG. 24 is an example flow diagram showing MCS UE 1 (2411) engaged inseparate MCS group calls with MCS UE 2 (2412) and MCS UE 3 (2413). AnMCS UE, may for example, may be a mission critical push-to-talk (MCPTT)UE. A first off-network mission critical (ONMC) wireless device maydiscover a plurality of ONMC wireless devices employing a proximityservices (ProSe) discovery procedure. The plurality of ONMC wirelessdevices may comprise, as illustrated in this example, MCS UE 1 (2411),MCS UE 2 (2412), and MCS UE 3 (2413).

MCS UE 1 (2411) and MCS UE 2 (2412) may be engaged in an MCS affiliatedgroup call at 2420. An affiliated group may comprise a group that has aconnection with an organization or other body. The connection may bewith a larger or more established group or organization. The connectionmay be with a smaller group or institution such as, for example, asubordinate part of an organization, a club, a branch organization,combinations thereof, and/or the like. An affiliated group may alsocomprise a group of people, institutions, etc., organized together onthe basis of a common purpose or of certain shared characteristics. So,for example, MSC UE1 (2411) and MSC (2412) may both be part of anaffiliated group, where MSC UE1 (2411) is part of a fire department andMSC UE2 (2412) is part of a police department affiliated with the firedepartment.

MCS UE 1 (2411) and MCS UE 3 (2413) may be engaged in an MCS affiliatedgroup call at 2430. An affiliated group call may comprise a call thatincludes members of two or more affiliated groups, such as, for example,a police group, a firefighter group and a paramedic group. For example,the first ONMC wireless device (MSC UE 1 2411) may transmit first mediatraffic, employing a first mission critical session, to the third ONMCwireless device (MSC UE 3 2413). A mission critical session is a missioncritical communication among one or more MSC UEs.

MCS UE 1 (2411) may get media from both MCS groups while transmittingmedia to one of the MCS groups at 2440. Examples of media include, butare not limited to, voice media, video media, data media, message media,combinations thereof, and/or the like. For example, a first ONMCwireless device (e.g. MCS UE 1 2411) may receive from the second ONMCwireless device (e.g. MCS UE 2 2412), a message comprising anorganization field identifier and an organization ID. An organizationfield identifier may identify the existence of a parameter for anorganization ID. An organization ID may identify, for example, a policedepartment, a fire department, a paramedic department, a combinationthereof, and/or the like.

MCS UE 2 (2412) may construct a floor request message with a highpriority at 2450. A floor request may comprise a request for permissionto transmit media. A high priority is a priority value that is greaterthan an average priority value for floor requests among the MSC UEdevices of an affiliated group. The floor request message may alsocomprise an organization ID. An organization ID may be unique for anorganization within an affiliated group.

According to an embodiment, first ONMC wireless device (e.g. MCS UE 12411) may determine a call priority, at least in part, based on theorganization field identifier and the organization ID. MCS UE 1 (2411)may suspend an MCS group call with MCS UE 3 (2413) to have a full mediaexchange with MCS UE 2 (2412) at 2460. Suspending (or otherwiseterminating) a call may occur to allow a higher priority call. Thehigher priority call may be from a closely affiliated organization. Forexample, transmission of the first media traffic to the third wirelessdevice may be terminated based at least on the call priority. Accordingto an embodiment, the first ONMC wireless device (e.g. MCS UE 1 2411)may start transmission of a second media traffic to the second ONMCwireless device (e.g. MCS UE 2 2412) employing a second mission criticalsession.

Although this example employs MCS UE's, embodiments are not so limited.It is envisioned that an MCS UE may be, for example, a mission criticalvideo UE, a mission critical audio UE, a mission critical message UE, amission critical push-to-talk (MCPTT) UE, a mission critical media UE,combinations thereof, and/or the like. So for example, when the MSC UEis a MCPTT UE, an MCPTT UE 1 (e.g. 2411) may receive media from bothaffiliated groups while transmitting to one affiliated group. The MCPTTservice may allow an MCPTT UE to be receiving or transmitting in oneMCPTT group while simultaneously receiving additional MCPTT groups. AnMCPTT UE 2 (e.g. 2412) may construct a floor request message with highpriority and may target MCPTT UE1 (2411). Upon receipt of the floorrequest message, MCPTT UE 1 (e.g. 2411) may determine the request'spriority and the MCPTT UE 2 (e.g. 2412) organization identity from afloor priority parameter or another optional parameter. MCPTT UE 1 (e.g.2411) may have a closer affiliation with MCPTT UE 2 (e.g. 2412) than theone with MCPTT UE 3 (e.g. 2413) and may suspend the MCPTT group callwith MCPTT UE 3 (e.g. 2413). Subsequently, MCPTT UE1 (e.g. 2411) andMCPTT UE 2 (e.g. 2412) may exchange media.

According to various embodiments, a wireless device may comprise one ormore processors and memory. The memory may store instructions that, whenexecuted by the one or more processors, cause the device to perform aseries of actions. Embodiments of example actions are illustrated in theaccompanying figures and specification.

FIG. 25 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2510, a first off-network mission critical(ONMC) wireless device may discover a plurality of ONMC wireless devicesemploying a proximity services (ProSe) discovery procedure. Theplurality of ONMC wireless devices may comprise a second ONMC wirelessdevice and a third ONMC wireless device. The first ONMC wireless devicemay be associated with, for example, a first group identified by a firstgroup identifier. The second ONMC wireless device may be associatedwith, for example, a second group identified by a second groupidentifier. According to an embodiment, the first wireless device; thesecond wireless device; and the third wireless device may communicatedirectly with each other without any network involvement.

The first group and the second group may be affiliated groups. Anaffiliated group may comprise a group that has a connection with anorganization or other body. The connection may be with a larger or moreestablished group or organization. The connection may be with a smallergroup or institution such as, for example, a subordinate part of anorganization, a club, a branch organization, combinations thereof,and/or the like. An affiliated group may also comprise a group ofpeople, institutions, etc., organized together on the basis of a commonpurpose or of certain shared characteristics.

At 2520, first media traffic may be transmitted by the first ONMCwireless device to the third ONMC wireless device employing a firstmission critical session.

At 2530, a message may be received by the first ONMC wireless devicefrom the second ONMC wireless device. The message may comprise anorganization field identifier and an organization identifier. Theorganization field identifier and/or the organization identifier mayindicate a closer affiliation between the first ONMC wireless device andthe second ONMC wireless device, compared with an affiliation betweenthe first ONMC wireless device and the third ONMC wireless device. Themessage may comprise, for example, a floor request message. The messagemay further comprise, for example, an organization length field.

At 2540, the first ONMC wireless device may determine a call priority,at least in part, based on the organization field identifier and theorganization identifier. The determining the call priority may indicate,for example, that the call priority is higher than a priority of thefirst media traffic.

At 2550, the first ONMC wireless device may terminate transmission ofthe first media traffic to the third wireless device, based at least onthe call priority. At 2560, the first ONMC wireless device may starttransmission of second media traffic to the second ONMC wireless deviceemploying a second mission critical session. At least one of the firstmedia traffic and the second media traffic may comprise, for example, atleast one of voice traffic, video traffic, or data traffic. According toan embodiment, the first ONMC wireless device may further receive, byfrom the second wireless device, a second group identifier of a secondgroup associated with the second ONMC wireless device. According to anembodiment, the first ONMC wireless device may further receive asecond-floor control message comprising a floor priority.

In this specification, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” In this specification,the term “may” is to be interpreted as “may, for example.” In otherwords, the term “may” is indicative that the phrase following the term“may” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various embodiments.If A and B are sets and every element of A is also an element of B, A iscalled a subset of B. In this specification, only non-empty sets andsubsets are considered. For example, possible subsets of B={cell1,cell2} are: {cell1},{cell2}, and {cell1, cell2}.

In this specification, parameters (Information elements: IEs) maycomprise one or more objects, and each of those objects may comprise oneor more other objects. For example, if parameter (IE) N comprisesparameter (IE) M, and parameter (IE) M comprises parameter (IE) K, andparameter (IE) K comprises parameter (information element) J, then, forexample, N comprises K, and N comprises J. In an example embodiment,when one or more messages comprise a plurality of parameters, it impliesthat a parameter in the plurality of parameters is in at least one ofthe one or more messages, but does not have to be in each of the one ormore messages.

Many of the elements described in the disclosed embodiments may beimplemented as modules. A module is defined here as an isolatableelement that performs a defined function and has a defined interface toother elements. The modules described in this disclosure may beimplemented in hardware, software in combination with hardware,firmware, wetware (i.e hardware with a biological element) or acombination thereof, all of which are behaviorally equivalent. Forexample, modules may be implemented as a software routine written in acomputer language configured to be executed by a hardware machine (suchas C, C++, Fortran, Java, Basic, Matlab or the like) or amodeling/simulation program such as Simulink, Stateflow, GNU Octave, orLabVIEWMathScript. Additionally, it may be possible to implement modulesusing physical hardware that incorporates discrete or programmableanalog, digital and/or quantum hardware. Examples of programmablehardware comprise: computers, microcontrollers, microprocessors,application-specific integrated circuits (ASICs); field programmablegate arrays (FPGAs); and complex programmable logic devices (CPLDs).Computers, microcontrollers and microprocessors are programmed usinglanguages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDsare often programmed using hardware description languages (HDL) such asVHSIC hardware description language (VHDL) or Verilog that configureconnections between internal hardware modules with lesser functionalityon a programmable device. Finally, it needs to be emphasized that theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the spirit and scope. In fact, after reading theabove description, it will be apparent to one skilled in the relevantart(s) how to implement alternative embodiments. Thus, the presentembodiments should not be limited by any of the above describedexemplary embodiments. In particular, it should be noted that, forexample purposes, the above explanation has focused on mission criticalservices such as mission critical push-to-talk services employing mediatypes such as audio services, video services and media services.However, one skilled in the art will recognize that embodiments of theinvention may also be implemented in a system comprising other types ofservices such as, for example, data services, augmented realityservices, data fusion services, combinations thereof, and/or the like.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposesonly. The disclosed architecture is sufficiently flexible andconfigurable, such that it may be utilized in ways other than thatshown. For example, the actions listed in any flowchart may bere-ordered or only optionally used in some embodiments.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112. Claims that do not expressly include the phrase “means for”or “step for” are not to be interpreted under 35 U.S.C. 112.

1. A method comprising: transmitting, by a first off-network wireless device to a third off-network wireless device, first media traffic employing a first session; receiving, by the first off-network wireless device from a second off-network wireless device, a floor request message comprising an organization field identifier and an organization identifier; determining, by the first off-network wireless device, a call priority, based on the organization field identifier and the organization identifier; terminating, based on the call priority, transmission of the first media traffic to the third off-network wireless device; and starting transmission, by the first off-network wireless device, of second media traffic to the second off-network wireless device employing a second session.
 2. The method of claim 1, wherein: the first off-network wireless device is associated with a first group identified by a first group identifier; the second off-network wireless device is associated with a second group identified by a second group identifier; and the first group and the second group are affiliated groups.
 3. The method of claim 1, further comprising receiving, from the second off-network wireless device, a second group identifier of a second group associated with the second off-network wireless device.
 4. The method of claim 1, wherein the determining the call priority indicates that the call priority is higher than a priority of the first media traffic.
 5. The method of claim 1, wherein the organization field identifier and the organization identifier indicate a closer affiliation between the first off-network wireless device and the second off-network wireless device, compared with an affiliation between the first off-network wireless device and the third off-network wireless device.
 6. The method of claim 1, wherein at least one of the first media traffic and the second media traffic comprises at least one of voice traffic, video traffic, or data traffic.
 7. The method of claim 1, wherein the organization identifier is an optional parameter in the floor request message.
 8. The method of claim 1, wherein the following communicate directly with each other without any network involvement: the first off-network wireless device; the second off-network wireless device; and the third off-network wireless device.
 9. The method of claim 1, wherein the floor request message further comprises an organization length field.
 10. The method of claim 1, further comprising receiving a second-floor control message comprising a floor priority.
 11. A first off-network wireless device comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the first off-network wireless device to: transmit to a third off-network wireless device, first media traffic employing a first session; receive from a second off-network wireless device, a floor request message comprising an organization field identifier and an organization identifier; determine a call priority, based on the organization field identifier and the organization identifier; terminate, based on the call priority, transmission of the first media traffic to the third off-network wireless device; and start transmission of second media traffic to the second off-network wireless device employing a second session.
 12. The first off-network wireless device of claim 11, wherein: the first off-network wireless device is associated with a first group identified by a first group identifier; the second off-network wireless device is associated with a second group identified by a second group identifier; and the first group and the second group are affiliated groups.
 13. The first off-network wireless device of claim 11, wherein the instructions, when executed by the one or more processors, further cause the first off-network wireless device to receive from the second off-network wireless device, a second group identifier of a second group associated with the second off-network wireless device.
 14. The first off-network wireless device of claim 11, wherein the call priority indicates that the call priority is higher than a priority of the first media traffic.
 15. The first off-network wireless device of claim 11, wherein the organization field identifier and the organization identifier indicate a closer affiliation between the first off-network wireless device and the second off-network wireless device, compared with an affiliation between the first off-network wireless device and the third off-network wireless device.
 16. The first off-network wireless device of claim 11, wherein at least one of the first media traffic and the second media traffic comprises at least one of voice traffic, video traffic, or data traffic.
 17. The first off-network wireless device of claim 11, wherein the following communicate directly with each other without any network involvement: the first off-network wireless device; the second off-network wireless device; and the third off-network wireless device.
 18. The first off-network wireless device of claim 11, wherein the floor request message further comprises an organization length field.
 19. The first off-network wireless device of claim 11, wherein the instructions, when executed by the one or more processors, further cause the first off-network wireless device to receive a second-floor control message comprising a floor priority.
 20. A method for use in a first off-network wireless device, the method comprising: transmitting, by a first off-network wireless device to a third off-network wireless device, first media traffic employing a first session; receiving, by the first off-network wireless device from a second off-network wireless device, a floor request message comprising an organization field identifier and an organization identifier; determining, by the first off-network wireless device, a call priority, based on the organization field identifier and the organization identifier; terminating, based on the call priority, transmission of the first media traffic to the third off-network wireless device; and starting transmission, by the first off-network wireless device, of second media traffic to the second off-network wireless device employing a second session. 